Heat exchanger



Nov. 29, 1938. Q M BARCLAY ET AL 2,138,469

HEAT EXCHANGER Filed Aug. 21, '1955 5 Sheets-Sheet l H 's s. lz Q Q t;Immun l|| J T L INVENTORS NOV. 29, 1938. M, BARCLAY ET AL 2,138,469

HEAT EXCHANGER Filed Aug. 2l, 1935 3 Sheets-Sheet 2 'Q' i s$ INVENTORS 0.ja/7n M Barc/oy -Jame5 B. 1ro/"bas ATTO EY Nov. 29, 1938". J. M.BARCLAY ET AL HEAT EXCHANGER Filed Aug. 2l, 1935 5 Sheets-Sheet 3INVENTORS o `/0/7/7 /l/l. Barc/oy 0K Jam es 5. Erbes ldt HEMI' EXCGIERJohn ll/ll. Barclay, Brooklyn, and .l'ames B. `Forbes, Mount Vernon, N.Y., assignors to Alec lrod-4 ucts incorporated, New York, N. Y., acorporation of Delaware Application August 2l, 1935, Serial No. 37,142

4l Claims.

Our invention relates to shell and tube heat exchangers and moreparticularly to improvements in the construction and arrangement ofinlet nozzles for directing Vapor or liquid into the shell space inwhich the exchanger tubes are located.

A type of heat exchanger commonly used in many industries, particularlyin the refining of petroleum is that comprising a number of parallel,serially connected tube bundles enclosed by a shell. A hot liquid orvapor to be cooled is caused to iiow at high velocity into` the shelland around the tubes through which 'ows a cooler liquid. The tubes aresecured to a fixed tube sheet at one end of the shell and to a floatingtube sheet at the other end. The nozzle for feeding the hot fluid intothe shell is frequently located at one end of the shell adjacent the xedtube sheet in which the tubes are mount- 0 ed. Within the shell andtransverse to the tubes are generally positioned a number of baiileplates. The tubes carrying the cooling liquid pass through enlargedholes in these baiiles, so that hot vapor in passing through theseopenings closely contacts the tubes and is more efficiently cooled.Obviously, it is desirable to provide such baffling throughout thelength of the tubes for greatest eiciency. However, when the usual typeof straight tubular inlet nozzle is positioned at the end of the shelladjacent the fixed tube sheet, the number of baiiies permissible at thatend is limited since the nozzle shape particularly because of thebolting anges necessitates positioning the nozzle and therefore theshell opening at some distance from the xed tube sheet and, of course,from the adjoining ends of the tubes. Because of this, the desiredcontact of vapors with the full length of the tubes is not attained andsome stagnation and pocketing of 40 the vapors in the shell occursadjacent the iixed tube sheet.

A further objection to the use of the conven-v tional type `'of straighttubular inlet nozzle' construction is that erosion of the tubes iscaused by direct high velocity impingement of the hot fluid on thetubes. The fluids ordinarily met with in petroleum refining carrysuflicient calcareous and other solid matter to render the erosioneffect of importance. Obviously, the gradual wearing down of the tubesonly hastens the time when the exchanger must be shut down for tubereplacement.

Itis an object of our invention to overcome these disadvantages in asimple and expeditious manner.

It is an object of our, invention to permit the effective use oftransverse bailies in portions of a heat exchanger shell where suchbailles were heretofore ineffective or incapable of being used.

It is another object of our invention to provide a heat exchangerconstruction promoting eihcient contact of the hot vapors throughout thelength or the cooling tubes and reducing the undesirable formation ofslow moving quantities of hot vapors' adjacentv the'vregion ofr vaporintroduction.

It is a furtherobject of our invention to effectively reduce the inletvelocity of .the hot vapors entering a heat exchanger shell and preventthe direct impingement of these high `ve-v locity vapors on the coolingtubes.

It is still another object of our invention to` appreciably reduce theerosion caused by mpingement of hot vapors on the tubes of a heatexchanger.

Other and further objects of our invention will appear from thefollowing description and appended claims.

In the accompanying drawings, which form part of the instantspecification and are to be read in conjunction therewith, and in whichlike numerals refer to like parts throughout the several views;

Figure 1 is a longitudinal part sectional View in elevation with partsomitted of a heat exchanger embodying a preferred form of inlet.

Figure 2 is an end view of the heat exchanger l of Figure 1.

Figure 3 is a plan view of the nozzle shown in Figure 1.

Figure 4 is a view in elevation of a cross section of part of a heatexchanger embodying a modified form of our invention.

Figure 5 is a view taken along the line 5-5 of Figure 4.

Figure 6 is a longitudinal part sectional View in elevation with partsomitted of a heat exchanger embodying another form of our invention.

Figure 7 is an end view of the heat exchanger shown in Figure 6.

Figure 8 is a view showing the arrangement of the vapor inlet openingsin the heat exchanger shell of Figure 6.

In general, our invention comprises a combined distribution andimpingement baille in conjunction with an inlet nozzle having a tubularentrance orneck portion formed integrally with an expansion or bodyportion of appreciably larger cross sectional area. 'I'he velocity ofthe vapor fed through the entrance portion of the nozzle is rapidlyreduced in the body portion due to expansion occurring in the greatervolume of the body portion of the nozzle. The body portion of the nozzleis fastened to the shell of a heat exchanger and communicates through anopenv ing in the shell with the interior. The vapor passing through thenozzle impinges on a baille which may be a portion of the shell or amember separate therefrom and thereafter ows laterally around the tubesin the shell. Direct impingeance of bolting operations.

ment of high velocity vapors on the tubes is thus avoided. y

Where the inlet nozzle is employed adjacent one end of the exchanger,the nozzle is formed with its tubular entrance or neck portion locatedat one side of its body or expansion portion. This formation permitslocating the orifice through which vapor enters the exchanger shell at aregion closer to the fixed tube sheet than would be practical with aconventional straight tubular type of inlet nozzle construction. Thisfollows by reason of the fact that the orifice over which a conventionaltype nozzle is positioned must be located sufciently far from the headeror channel of the exchanger that the bolting flange of the nozzle willnot prevent access to adjacent portions of the exchanger header for theperform- Obviously, as the orifice is moved farther from the fixed tubesheet of the header, the space available for baffles is reduced, whereasthe present invention enables the employment of additional baflles andthe elimination of previous bolting problem. In addition, theimpingement baille, against which the vapors flowing through the nozzleare directed,

assists the flow of vapor around the tube portion adjacent the xed tubesheet, thus promoting more efficient heat exchange in these portionsthrough vapor contact.

Referring now more particularly to the drawings, a xed'tube sheet 3, inwhich the tubes 2 are thereby fxedly held at one end, is clamped betweena flange 4 of the shell I and a channel ring removably fastened to theflange 4 by a plurality of bolts or other suitable clamping devices 6.The opposite ends of the tubes 2 are fastened in a conventional mannerto a floating header (not shown). A channel cover plate 1 is removablyattached to the channel 5 by means of a plurality of peripherallydisposed bolts or other suitable clamping devices 8. The channel ring 5,xed tube sheet 3 and cover plate 'I together form a fixed header forpassing cooling fluid through the tubes 2, this header being internallydivided into a pair of compartments (not shown) by an imperforatepartition member (not shown).

It will be obvious from the foregoing that a flow of cooling fluidthrough the tubes 2 may be effected in accordance with conventionalpractice. Thus, cooling fluid fed into one of the pair of compartmentsin the fixed header will flow through the tubes 2 communicatingtherewith, through the floating header, and through the remainder of thetubes 2 into the other compartment of the pair with which theycommunicate.

A nozzle BI, for feeding cooling oil, or other suitable cooling fluidinto one of the pair of fixed header compartments, is fastened to thechannel 5 and communicates through an opening therein with one of thepair of compartments of the flxed header. A nozzle SI, for withdrawingthe cooling oil from the other of the pair of flxed header compartmentsafter passage of the oil through the tubes 2, is fastened to the channel5 and communicates through an opening therein with the other of the pairof fixed header compartments.

The floating head end of the shell is covered by means of a cap I0removably fastened to a flange II of the shell by bolts or suitableclamping means I2.

Referring now more particularly to Fig. 1, a plurality of baflies I3formed with openings through which the tubes y2 pass are positionedtransversely of and Within the shell I and spaced from each other by anumber of spacer tubes I4 through which run the tie rods I5 fastened atone end to the fixed tube sheet 3 as is best shown in Fig. 4. Theopenings in each baille through which the tubes 2 pass are larger thanthe tubes, with the openings in succeeding baffles arranged in staggeredformation to secure a vapor flow across the tubes. The arrangement ofthese openings may take many forms and forms no part of our invention.

A vapor inlet nozzle I6 having a generally tubular entrance or neckportion I'I formed integrally with an enlarged expansion or body portionI8, as shown, is fastened'to the shell I as by welding or in any othersuitable manner and communicates with the shell space through an openingI9 formed in the shell between the fixed tube sheet 3 and the first ofthe series of transverse baffles I3.

In Figure l, which shows a preferred embodi- .ment of our invention, wehave shown the nozzle I6 having its tubular entrance portion I'Ipositioned directly over a section of the shell I.

In this form of nozzle, the neck or entrance portion II is positioned atone side of the enlarged expansion or body portion I8 which lattercommunicates with the opening I9. The portion 20 of the shell I alsoenclosed by the body portion serves as an impingement and distributionbaille. A vapor outlet nozzle 24 communicates with the shell spacethrough an opening in the shell I at the floating head end of the shell.

In Figures 4 and 5, We have shown a modified form of impingement anddistribution baille 20 having flanged side edges 2| fxedly attached asby welding to a pair of the spacing tubes I4 thus spacing the bafflefrom and positioning it within the shell I directly below the tubularentrance or neck portion II of the nozzle I6. The anged edges 2| of thebaille press tightly against the inner surface of the shell, while therear un flanged `edge abuts the first of the series of transversebailles I3. In this form of construction, that portion of the shell inthe area embraced by the enlarged expansion or body portion I8 of thenozzle is removed to form a vapor opening in the shell. The arrangementof the impingement baflie 20 as a separate member within permits itsremoval for cleaning with the cooling tubes 2 and transverse bales I3.

In Figures 6, 7, and 8, we have shown still another modification of ourinvention in which the nozzle I6 is fastened to the shell Isubstantially centrally thereof. The shell within the area embraced bythe enlarged expansion or body portion I8 of the nozzle is formed with aplurality of vapor inlet openings 22 circumferentially disposed about aportion of the shell forming a central imperforate impingement baille 20positioned directly below the inlet portion I'I of the nozzle. The shellspace is internally divided, by a central imperforate transversepartition 22 and a central longitudinal partition 23 spaced from theshell ends into a number of compartments as shown. A vapor outlet nozzle24 communicates with the compartments through an opening 25 in theshell.

In the operation of the heat exchanger shown in Figures 1 5 hotpetroleum vapor enters the nozzle I6 at considerable velocity throughthe entrance or neck portion I 1 and expands in the enlarged expansionor body portion I8 and through the opening I9 in the shell withattendant reduction in velocity. The vapors striking the impingement anddistribution baille 20 in Figs. 1

and 3 and impingement baiile 20' in Figs. 4 and 5 are camed to iiowlaterally around the cooling tubes 2 between the first baie I2 and thefixed tube sheet 3 and toward said tube sheet. The vapors are redirectedby the tube sheet along the tubes through the transverse baflies I3 andare eventually removed through the discharge opening 25 and nozzle 24.It will be observed that by this construction direct impingement of highvelocity vapors on the cooling tubes is prevented, erosion is reducedand tube life is prolonged. In addition, the longitudinal movement ofthe lower velocity vapors along the tubes adjacent the fixed tube sheetresults in more effective use of this portion of the cooling tubes thanhas heretofore existed. Also, by virtue of the laterally offsetarrangement of the base portion inlet nozzle, it is possible to locatethe opening into the shell closer to the tube sheet than was practicalwith conventional nozzle constructions heretofore. This permits theinsertion of additional transverse baille means with resultant greaterefficiency of heat transfer through better control of vapor ow.

In the modification shown in Figure 6, the impingement baille 20functions in the same-manner as in Figures 1-4, the vapors at reducedvelocity flowing through the openings I9 in all directions into theshell space through which they travel and are discharged through opening25 and nozzle 24 in the manner shown. However, in this modification, theimpingement baffle does not function mainly to distribute the vaporsalong the cooling tubes, but mainly to reduce the vapor velocity andthus prevent erosion of the tubes.

Although we have described' our invention with relation to the flow ofvapor through the heat exchanger, it is to be understood that the use ofsuch term is not intended to be restrictive as our invention isapplicable to handling of fluids in general whether liquid, vapor orgas.

It will be understood that certain features and subcombinations are ofutility and may be employed without reference to other features andsub-combinations. Ihis is contemplated by and is within the scope of ourclaims. It is further obvious that various changes may be made indetails within the scope of our claims without departing from the spiritof our invention. It is, therefore, to be understood that our inven--tion is not to be limited to the specific details shown and described.

Having thus described our invention, what is claimed is:

1. A heat exchanger comprising in combination, a shell; a heaar sealingone end of said shell; a tube bundle in said shell connected to saidheader; a series of bailies within said shell transverse to the tubes ofsaid bundle; an orifice in the periphery of said shell between saidheader and said series of baffles; means other than said shell forming anozzle fastened to said shell at a locus wholly spaced from either endof said shell for feeding fluid through said orifice, said nozzle meanshaving a neck portion and an enlarged body portion integral with saidneck portion; said body portion being positioned over said orifice andsaid neck portion being joined to said body portion at a region farthestremoved from said header; and, an impingement baiiie longitudinallypositioned between said tube bundle and said shell ,to receive fluiddischarged through said orifice and to direct the fluid along the tubestoward said header, said impingement baille being carried by said tubebundle.

2. A heat exchanger comprising in combination, a shell; a header sealingone end of said shell; a tube bundle in said shell connected to saidheader, said tube bundle being removable from said shell; a series ofbafiles within said shell transverse to the tubes of said bundle; anorifice in the periphery of said shell between said header and saidseries of bafiles; means other than said shell forming a nozzle fastenedto said shell at a locus wholly spaced from either end of said shell forfeeding fluid through said orifice, said nozzle means having a neckportion and an enlarged body portion integral with said neck portion,said body portion being positioned over `from said header; and, animpingement baille longitudinally positioned between said tube bundleand said shell to receive iiuid discharged through said orifice and todirect the uid along the tubes toward said header, said impingement'baiile being supported by said tube bundle and being removabletherewith.

3. A heat exchanger comprising in combination, a shell; av headersealing one end of said shell; a tube bundle in said shell connected tosaid header; a series of baiiles within said shell transverse to thetubes of said bundle; an orifice in the periphery of said shell betweensaid header and said series of bales; means other than said shellforming a nozzle fastened to said shell at a locus wholly spaced fromeither end of said shell for feeding fluid through said orifice, saidnozzle means having a neck portion and an enlarged body portion integralwith said neck portion, said body portion being positioned over saidorifice and said neck portion being joined to said body portion at aregion farthest removed from said header; and, an impingement baielongitudinally positioned between said tube bundle and said shell toreceive fluid discharged through said orifice and to direct the Huidalong the tubes toward said header, said impingement bale having one endabutting the first baflie of said series of transverse baiiies andhaving fianged edge portions abutting said shell at opposite sides ofsaid orifice.

4. A heat exchanger comprising in combination, a shell; a header sealingone end ofsaid shell; a tube bundle in said shell connected to saidheader; a series of baiiles within said shell transverse to the tubes ofsaid bundle, the first baille of said series being spaced from saidheader by tubular spacing collars; an orifice in the periphery of saidshell between said header and said series of baflies; means other thansaid shell forming a nozzle fastened to said shell at a locus whollyspaced from either end of said shell for feeding fluid through saidorice, said nozzle means having a neck portion and an enlarged bodyportion integral with said neck portion, said body portion beingpositioned over said orifice and said neck portion being joined to saidbody portion at a region farthest removed from said header; and, animpingement baffle longitudinally positioned between said tube bundleand said shell to receive iiuid discharged through said orifice and todirect the fiuid along the tubes toward said header, said impingementbaiile

